What Can I Do To Calm Myself Down?

I have a really hard midterm in almost 4 hours. It's in a nutrition cl (which is a really hard cl to begin with.) and I'm really, incredibly nervous. I've been studying really hard for this test, and know the material pretty well, but (and I'm not using this an excuse or anything or to whine and complain) I do have learning disabilities, and taking tests (especially college tests) is very difficult for me. I always have trouble comprehending what the questions are asking me, and I also have trouble understanding really big words (which my nutrition cl has a lot of.) I'm going to be perfectly honest, I even had to use the method of studying that my mom taught me when I was in elementary school. And that was, to make up corny phrases that I would remember. (Like the common corny phrase to remember the colors of the rainbow Roy G. Biv, stuff like that.) I've thought of some pretty good ones too. But still, as many awesome corny phrases as I've thought up, I'm still incredibly nervous, and I'm afraid I'll freeze up and forget everything. I'm also more afraid that while I'm taking my test I'll have a seizure (I have Epilepsy, and I've been having tons and tons of seizures lately. I had one just last week, and it happened to be right in front of the guy I have a huge crush on, but he didn't happen to see anything. I mean I know if he did see, he probably would've come over and stayed with me to make sure I was ok. But when I have a seizure, I will blank out, and then I will get up and walk around the room like I were sleep walking. I've had it all my life, but I'm being treated. I'm on 4 different meds. for it, and I just got put on a new one a couple weeks ago. But still, that would be so embarring if I happened to get up and walk around the room and possibly wander out the door while people are taking a test! :O) and totally embarr myself! I am just so incredibly nervous and I don't know how to calm down! Please help!